Certification of passive houses: Lessons from real indoor climate systems

This paper examines if and how indoor climate systems are important for passive house certification. The research subjects are passive houses in Belgium, occupied by owner-clients. These have received a quality assurance certificate from an independent organization. Through interviews with the owners, and on-site analysis of indoor climate installations in passive houses, the selection of indoor climate systems for passive houses was analyzed and insights were obtained in changes occurring after certification. Also, two houses were analyzed during further visits, including interviews and measurements, to allow detailed performance evaluation of the indoor climate systems. The paper concludes that adaptation of certification procedures is recommended, by looking more closely at the practical implementation of indoor climate systems. The paper further questions the general validity of the scientific basis of the passive house definition